From: "Doug Ewell" <[EMAIL PROTECTED]> > Michael Everson <everson at evertype dot com> wrote: > > > There is no such thing as a semi-private character. There are > > standardized characters (which have particular meanings), and there > > are private use characters (which are guaranteed to have no meanings > > at all). > > I thought PUA characters had very specific meanings, defined by the > private parties who assign them, but utterly ignored by the standard. > > What Philippe may have meant by "semi-private characters" is "characters > whose privately assigned meanings have been publicized." This would > include CSUR scripts, Apple's and Microsoft's assorted ligatures and > dingbats, and William Overington's stuff.
As well as the many logographic characters that can be interchanged in some limited ways, with conditions, and will not fit with the strict open model needed by Unicode as they may be covered by copyrights or digital rights. The existence of these restrictions, which limits, but in fact does not forbid interchanges of information is a grey area currently not covered either by PUAs (not interchangeable), and by regulated parts of Unicode due to its policy. This is a place where limited agreements managed by a registration authority could help avoid conflicts of assignments, simply not possible with PUA.

